Noun
analog signal (plural analog signals)
English Wikipedia has an article on:analog signalWikipedia
A signal that can vary in a continuous manner (as opposed to a digital signal that only takes discrete values).
Analog signal generators An analog RF signal generator Analog signal generators based on a sine-wave oscillator were common before the inception of digital electronics, and are still used. Source: Internet
Analog signal processing (ASP) then involves physically altering the continuous signal by changing the voltage or current or charge via various electrical means. Source: Internet